With constantly changing climate, freezing of seawater alongside Bohai Bay not only threatens the trips of fishing boats, but also results in serious freeze-thaw damage to concrete structure along the beach and at sea. In the cold area of northern China, in order to ensure traffic safety, deicing salt is used to melt snow in winter; the thermal shock of deicing salt leads to the freeze-thaw damage on the concrete bridge surface or the road surface. The typical characteristic of freeze-thaw damage of concrete is the spalling of surface concrete. Obviously, the surface spalling of land concrete can be observed by unaided eyes, while the structure concrete at the bottom of offshore engineering is just the opposite, which goes against the timely maintenance of structure due to the difficulty of observation.
So far, no method for real time on-line monitoring of concrete freeze-thaw damage is disclosed.